Parser handler for "persistence.xml" files to convert them into a PersistenceFileMetaData.
Implements DefaultHandler and handles the extracting of MetaData from the
XML elements/attributes. This class simply constructs the MetaData representation
mirroring what is in the MetaData file.

Operates the parse process using a Stack. MetaData components are added
to the stack as they are encountered and created. They are then popped off
the stack when the end element is encountered.